V4L/DVB (11064): au8522: make use of hybrid framework so analog/digital demod can share state

Make use of the hybrid tuner framework so the analog and digital parts of the
au8522 demodulator can make use of the same shared state.

Thanks to Michael Krufky <mkrufky@linuxtv.org> and Steven Toth
<stoth@linuxtv.org> for providing sample hardware, engineering level support,
and testing.

Signed-off-by: Devin Heitmueller <dheitmueller@linuxtv.org>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>